Matilda of Scotland, the first wife of King Henry I of England died in May of 1118 and in November of 1120, Henry’s only son and heir William Adelin died in a tragic ship wreck. Henry was left with only his daughter Matilda as his heir and she was married to the German emperor Henry V. While it wasn’t impossible for a women to rule his kingdom, read more here: http://thefreelancehistorywriter.com/2015/03/20/adeliza-of-louvain-queen-of-england/